Solve for $p$ : $7 = p - 14$
Solution: Add $14$ to both sides: $ \begin{eqnarray} \\ \hphantom{7 {+ 14}} &\hphantom{=}& \hphantom{p} \\ 7 &=& p - 14 \\ \\ {+14} && {+14} \\ \end{eqnarray} $ $ \begin{eqnarray} \\ 7 {+ 14} &=& p \\ \end{eqnarray} $ Simplify. $ p = 21$